Scarce Heath (Coenonympha hero)

Scarce Heath (Coenonympha hero)

The Scarce Heath is a delicate and uncommon species of satyrid butterfly found in temperate parts of Europe and Asia. Preferring moist meadows and forest clearings, it is a rather elusive species that often goes unnoticed due to its quiet behavior and subtle coloring. Its rarity in many parts of its range makes it of significant conservation interest.

🦋 Identification

• Wingspan: 28–36 mm
• Flight: Weak and fluttery, close to vegetation

Appearance:

• Upperside: Uniform brown to orange-brown; not often seen as the butterfly usually rests with wings closed.
• Underside of hindwings:
  • Pale brown to greyish
  • Distinctive white band with a row of black eyespots (ocelli), each ringed with yellow
• Forewing underside: Orange-brown, often with lighter shading

Compared to similar species like the Small Heath (Coenonympha pamphilus), the Scarce Heath has a more sharply defined row of eyespots on the hindwing underside.

🌿 Habitat

• Prefers moist, sunny meadows, wet grasslands, and forest edges with tall herbaceous vegetation
• Often found in river valleys, boggy clearings, or damp pastures

The presence of host plants and a mosaic of open and semi-shaded areas is crucial.

🍽️ Diet

Caterpillars feed on grasses, including:

• Poa (bluegrass)
• Festuca (fescue)
• Possibly Molinia (purple moor-grass) and other damp-loving grasses

Adults:

• Feed on nectar from low-growing wildflowers, especially:
  • Buttercups
  • Vetches
  • Clovers
  • Wild thyme (regionally)

🔁 Behavior & Life Cycle

• Flight period:
  • Typically May to July, depending on latitude and altitude
• Voltinism:
  • Univoltine (one generation per year)

Life cycle:

• Eggs laid singly on or near host grasses
• Caterpillars develop slowly and overwinter in the larval stage
• Pupation occurs in spring, with adults emerging in early summer

Behavior:

• Males patrol low over vegetation for females
• Adults rest with closed wings and are difficult to spot
• Timid and rarely stray far from suitable habitat

🌍 Distribution

• Found in central and eastern Europe, extending into:
  • Russia, Ukraine, Baltic States
  • Scandinavia (locally)
  • Parts of northern and central Asia

Absent from much of western and southern Europe.

🧬 Interesting Facts

• The name “Scarce Heath” reflects its limited and fragmented distribution in much of Europe.
• Sensitive to habitat changes; survives best in traditional wet meadow systems.
• Part of a genus (Coenonympha) known for cryptic species with subtle wing differences.

🛡️ Conservation Status

• IUCN Red List: Least Concern (globally), but locally threatened or rare in parts of Europe
• Threats include:
  • Drainage of wetlands
  • Intensive agriculture
  • Habitat fragmentation
  • Succession due to cessation of traditional grazing or mowing

Conservation actions focus on:

• Preserving wet meadows
• Restoring traditional land management (mowing, grazing)
• Protecting known populations through habitat maintenance

The Scarce Heath (Coenonympha hero) is a quiet symbol of Europe’s wet grasslands and forest glades. Its understated beauty and sensitivity to ecological changes make it an important species for conservation, representing the delicate balance of semi-natural habitats.